Geochemistry of volcanogenic clayey marine sediments from the Hazar-Maden Basin (Eastern Turkey)

Abstract The Hazar-Madeıı Basin sediments were deposited along the southern branch of the Neotethys Ocean margin during Late Maastrichtian-Middle Eocene times. X-ray powder diffraction (XRD), ICP-AES, ICP-MS and scanning electron microscopy (SEM) were performed on samples of the Upper Maastrichtian-Middle Eocene Hazar Group and the Middle Eocene Maden Complex from the Hazar-Maden Basin to investigate the main effects of depositional envi- ronmental parameters in three sections belonging to deeper marine (slope), proximal arc volcanic (Mastarhill and Yukaribag sections) and shallow platform marine (Sebken section) settings. Marine sediments contain clay minerals (smectite, smectite/chlorite, chlorite, illite, interstratified illite/smectite, illite/chlorite, palygorskite), clinoptilolite, quartz, feldspar, calcite, dolomite, opal-CT and hematite. The clays are dominated by iron-rich smectites. La, Zr and Th concentrations are high in the shallow marginal Sebken section where the terrestrial detrital contribution is significant, while Sc and Co are more dominant in the deeper marine (slope) Yukaribag section, which is represented by basic-type volcanism and a higher contribution of hydrothermal phases. In a chondrite-normalized REE diagram, the negative Eu anomaly in samples from Sebken, the section which was deposited in a shallow marine environment, is less significant than that of the other two sections indicating the presence of a high terrestrial contribution in that part of the basin. A decrease in LREE v/HREEiV and Lajv/Ybv, LaiV/Sin v ratios from Sebken to Mastarhill and the Yukaribag sections indi- cates deepening of the basin and an increasing contribution of volcanism in that direction.

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Unusual seawater composition of the Late Cretaceous Tethys imprinted in glauconite of Narmada basin, central India

Geological Magazine ◽

10.1017/s0016756819000621 ◽

2019 ◽

Vol 157 (2) ◽

pp. 233-247 ◽

Cited By ~ 6

Author(s):

Udita Bansal ◽

Santanu Banerjee ◽

Kanchan Pande ◽

Dhiren K. Ruidas

Keyword(s):

Late Cretaceous ◽

Central India ◽

Shallow Marine ◽

X Ray ◽

Greenhouse Climate ◽

Ce Anomaly ◽

Eu Anomaly ◽

Tethys Ocean ◽

Depositional Setting ◽

Ree Pattern

AbstractA detailed investigation of a glauconite bed within the Late Cretaceous Bryozoan Limestone Formation of the Bagh Group in central India, as well as the study of existing records, reveals the existence of a ‘glauconitic sea’ along the margins of the Palaeo-Tethys Ocean during the Late Cretaceous Epoch. The authigenic green mineral formed abundantly on shallow seafloors unlike in its modern, deep-sea counterpart. We present an integrated petrographical, geochemical and mineralogical investigation of the glauconite within Late Cretaceous transgressive deposits to highlight its unique geochemistry with moderate Fe2O3 and high Al2O3, SiO2, MgO as well as K2O contents. X-ray diffractional parameters identify the ‘evolved to high evolved’ nature of the glauconite while Mössbauer spectroscopic study reveals the dominance of Fe3+ compared to Fe2+ in the atomic structure. The rare earth elements (REE) pattern of glauconite reveals moderate light-REE/heavy-REE (LREE/HREE) fractionation and weak negative Eu anomaly. The Ce anomaly of the glauconite indicates a sub-oxic diagenetic condition. We propose that Late Cretaceous glauconites formed within a shallow marine depositional setting across the Tethyan belt because of enhanced supply of K, Si, Al, Fe, Mg cations through continental weathering under the extant greenhouse climate.

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DETERMINATION OF NICKEL, ZINC AND COBALT IN ADVANCED MATERIALS BASED ON NixCo3–xO4 AND ZnxCo3–xO4 BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY (ICP-MS) AND X-RAY FLUORESCENCE

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2018-84-1-i-10-13 ◽

2018 ◽

Vol 84 (1) ◽

pp. 10-13 ◽

Cited By ~ 4

Author(s):

A. A. Krotova ◽

K. Ya. Prikhodko ◽

S. A. Vladimirova ◽

D. G. Filatova

Keyword(s):

Mass Spectrometry ◽

Inductively Coupled Plasma ◽

Advanced Materials ◽

X Ray ◽

Inductively Coupled ◽

Nickel Zinc ◽

Determination Of Nickel ◽

Icp Ms ◽

Plasma Mass Spectrometry

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Hingganite-(Nd), Nd2□Be2Si2O8(OH)2, a new gadolinite-supergroup mineral from Zagi Mountain, Pakistan

The Canadian Mineralogist ◽

10.3749/canmin.2000039 ◽

2020 ◽

Vol 58 (5) ◽

pp. 549-562

Author(s):

Anatoly V. Kasatkin ◽

Fabrizio Nestola ◽

Radek Škoda ◽

Nikita V. Chukanov ◽

Atali A. Agakhanov ◽

...

Keyword(s):

New Mineral ◽

Monoclinic Space Group ◽

X Ray Diffraction ◽

Average Chemical Composition ◽

X Ray ◽

Conchoidal Fracture ◽

Icp Ms ◽

Optical Axes ◽

Mohs Hardness ◽

Khyber Pakhtunkhwa Province

ABSTRACT Hingganite-(Nd), ideally Nd2□Be2Si2O8(OH)2, is a new gadolinite group, gadolinite supergroup mineral discovered at Zagi Mountain, near Kafoor Dheri, about 4 km S of Warsak and 30 km NW of Peshawar, Khyber Pakhtunkhwa Province, Pakistan. The new mineral forms zones measuring up to 1 × 1 mm2 in loose prismatic crystals up to 0.7 cm long, where it is intergrown with hingganite-(Y). Other associated minerals include aegirine, microcline, fergusonite-(Y), and zircon. Hingganite-(Nd) is dark greenish-brown, transparent, has vitreous luster and a white streak. It is brittle and has a conchoidal fracture. No cleavage or parting are observed. Mohs hardness is 5½–6. Dcalc. = 4.690 g/cm3. Hingganite-(Nd) is non-pleochroic, optically biaxial (+), α = 1.746(5), β = 1.766(5), γ = 1.792(6) (589 nm). 2Vmeas. = 80(7)°; 2Vcalc. = 84°. Dispersion of optical axes was not observed. The average chemical composition of hingganite-(Nd) is as follows (wt.%; electron microprobe, BeO, B2O3, and Lu2O3 content measured by LA-ICP-MS; H2O calculated by stoichiometry): BeO 9.64, CaO 0.45, MnO 0.10, FeO 3.03, B2O3 0.42, Y2O3 8.75, La2O3 1.63, Ce2O3 12.89, Pr2O3 3.09, Nd2O3 16.90, Sm2O3 5.97, Eu2O3 1.08, Gd2O3 5.15, Tb2O3 0.50, Dy2O3 2.50, Ho2O3 0.33, Er2O3 0.84, Tm2O3 0.10, Yb2O3 0.44, Lu2O3 0.04, ThO2 0.13, SiO2 23.55, H2O 2.72, total 100.25. The empirical formula calculated on the basis of 2 Si apfu is (Nd0.513Ce0.401Y0.395Sm0.175Gd0.145Pr0.096Dy0.068La0.051Ca0.041Eu0.031Er0.022Tb0.014Yb0.011Ho0.009Tm0.003Th0.003Lu0.001)Σ1.979(□0.778Fe2+0.215Mn0.007)Σ1.000(Be1.967B0.062)Σ2.029Si2O8.46(OH)1.54. Hingganite-(Nd) is monoclinic, space group P21/c with a = 4.77193(15), b = 7.6422(2), c = 9.9299(2) Å, β = 89.851(2)°, V = 362.123(14) Å3, and Z = 2. The strongest lines of the powder X-ray diffraction pattern [d, Å (I, %) (hkl)] are: 6.105 (95) (011), 4.959 (56) (002), 4.773 (100) (100), 3.462 (58) (102), 3.122 , 3.028 (61) (013), 2.864 (87) (121), 2.573 (89) (113). The crystal structure of hingganite-(Nd) was refined from single-crystal X-ray diffraction data to R = 0.034 for 2007 unique reflections with I > 2σ(I). The new mineral is named as an analogue of hingganite-(Y), hingganite-(Yb), and hingganite-(Ce), but with Nd dominant among the rare earth elements.

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